JD6620

I have a JD 6620 that I am harvesting Rye with for the first time. I am getting a lot of seed heads (without seeds) in the grain. The manual says to run the cleaning fan at 800=900 RPM for rye. If I increase the fan RPM over 300 I start to loose seed, and at 400 RPM essentially no seed comes out of the auger. The seed in the picture had a fan speed of 280. Any suggestions? Other things I need to be doing?

Thanks,
Rich

If it is like an IH with a top and bottom sieve, close the bottom sieve tighter. Also can more air be directed to the bottom sieve only? How fast the fan can run is highly dependent on how heavy the crop is or in other words the amount of material coming through the machine. If it can thresh the grain out of the heads drive faster. Also a more open top sieve can let the crop seed fall through better even though it lets more trash in. Just some common sense items to consider when setting a combine.

Used Red-

Thanks very much for you common sense suggestions/explanations...Very Helpful!

I completely close the bottom seive on my 7720 for wheat so maybe worth a try.

To add to what is said, I think your top sieve needs to be open a little more to let the grain in easier. the purpose of the fan is to float the material over the sieves, and I think at your RPM you are way too low, causing the mat of material to lay on the sieves vs float over the top. Rye seeds are small, but dense- 60 lb per bushel. they should not blow out easily even at the high fan speed.

If the manual says 900 and you are throwing it over at 300, I'd say try speeding it up to the recommended speed. It may seem counter intuitive, but try it with the fan speed turned up and at field speeds. You might be surprised. I usually run MORE than recommended fan on my 9500, don't get any more coming over the sieves, and a cleaner sample.

Last, make sure grain on the ground is not coming off the front of the combine, like a leak at the feederhouse or head. When you stop, crawl under the combine to look at the ground between the head and the rear of the machine- it will help you isolate leaks other than the back of the sieves. Grain can also carry over in the straw, so make sure that isn't the issue as well. Cylinder combines should have a curtain behind the cylinder to keep grain from being thrown back onto the straw, and then out the back. Make sure yours is in place.

Good luck, and let us know ow it turns out.

Thanks for the suggestion of closing the bottom sieve. I tinkered with it a bit and overall the seed ended up relatively clean...but could have been better. I will try your suggestion next time.
Thanks!
Rich

Very Helpful!! I am done with this years, but will keep your suggestions for the next round!

Thanks!
Rich